davelepka

If you mean that I personally have something against Atair, that would be wrong. My feelings are for the Cobalt, and they are based on personal experience with the canopy. In the spirit of this discussion, my responding to a guy with 80-some jumps advising against the Cobalt seems pretty reasonable. It's not the best choice at that experience level by far. Even beyond that, I feel there are much better canopies to choose if you're looking for a medium to high performance canopy at the WL's Atair reccomends. Whats not right about giving an honest answer to a question? I have demoed the Cobalt, and other canopies in it's class, they all got a fair shot. I wouldn't order a demo and actually jump a canopy if I didn't think the design had some promise.

If you're asking because you might want a Cobalt, don't. My experience with the Cobalt sucked, as have others. Some will say they love th eCobalt, but consider you is giving that advice, and what experiecne they have in general. When it comes to canopies, you cannot go wrong with PD. I've jumped alot of stuff, but only owned PD canopies, main and reserve. In all fairness, Icarus, Percision and Aerodyne seem to have some good things going, as well. Any of those four: Good choice. Atair / Cobalt : Not so good.

If you make a tool, and it breaks, and the rigger loses a finger, you might have a problem. What a rigger does with a rig under his or her care is their responsibility. This is what the riggers ticket is for. It's an end to the chain of responsibility, they are approved and rated as qualified to make 'executive' decisions regarding equipment and it's assembly or maintenence. You have no control nor knowledge of what the rigger will do with these tools. If they use a packing paddle to beat someone to death, would you fear liability in the death? Surely not. It's the same thing with rigging tools. How or even if the rigger uses the tools is out of your control. You will not get rich with this plan. What you may get is free rigging, which can be a pretty good deal. 90% of what a rigger charges is labor, so they can afford to give away a good bit of that in exchange for goods or services.

I think this thread is getting out of hand. There seems to be several slightly different issues being discussed at the same time. I'm really not sure if any of them are even worth the time we're putting into them. I'm pretty sure that everyone is right in some way, pretaining to their own topic, of course. What I will say is this: If anyone out there has some confusion about any of the topics, locate who is supporting your issue, and PM them with specific questions. Then take what they tell you, and run it by some senior jumpers at your DZ, then take it all with a grain of salt. None of this stuff is life threatening anyway. In the end, pulling the red handle will put all of these arguements to rest (unless you have a reserve mal, in which case, get tough, it's probably going to hurt).

If you are trying to illustrate a jumper leaning forward and back in a standard skydiving harness, your drawing is correct. Actually it does a good job of illustrating how the single point attachment will dampen out any weight shift forward or back.

What does full flight have to do with the rotational speed? I can see how a canopy could achieve equalibrium in a turn, and remain in the turn until a countering input is applied. I cannot understand how a symetrical release of the brakes will stop the turn. It is possible that eventually the turn may stop, as releasing the brakes will change the balance of the system, maybe to a state where the turn cannot 'power' istelf but I cannot see this as being anything close to immediate, and not a solution to a 'problem' situation. If you were in an AC in a spin, with flaps deployed, would your course of action include retracing them? I would apply rudder against the spin, to bring the stalled wing forward, and level the AC. The flaps would not enter the equation. Substitute the words 'brakes' for flaps, and 'toggle' or 'rear riser' for rudder, and you have the canopy version of the solution.

Yeah, I've seen those before. Thats the idea. Now we need to attach it to a harness so you can deploy it, cut it away, operate it without using your hands, and make sure everything happens symetrically. Like I said, someone else go first, I'll shoot video.

Yeah, I've found color to be the best indicator. The red ones are fast, like cars. Thats why canopies were slow in the 80's, they were all brown and green. Once neon colors came out, it was the beginning of the end.

I may have missed that part. Is the claim that by pulling the rears down, you are creating two attachment points (front to back), the three rings being the front, and your hands on the rears being the rear? If so, it's on the right track, that if you had two attachment points, and could shift weight from one the other, youcould alter the flight of the canopy. The problem is that by grabbing the rears, and 'creating' the rear attachment point, you are altering the canopy, before any weight shift can take place. This appears to be what is happening in the ground launch pics that Jim Slaton posted. While in that configuration, you may see a result coinciding with a weight shift, but thats a different set of circumsatnces, and without the 'added' attachment point, forward or rearward weight shift is not a factor. It's interesting how Brian Germains name is dropped left and right as 'the guy who wrote the book', and generally regarded as the end of the line for these sorts of disputes, but this thread soldiers on after he chimed in with the facts. Edit: What you would need to make this work is a mechanical device of some sort. Picture a pair of bars if you will, maybe three inches long, with the front riser attached to the front, and the rears to the back. These would rest on your shoulders, with an attachment to the harness (above the three ring) that allows for the bar to slide forward and back. When the bar is in the 'back' position, with the attachment point at the front of the bar, the canopy would be trimmed very steeply, for long dives (and big speed). Shifting the bar to the 'front' position would re-trim the enitre canopy, allowing it to plane out with no other (speed robbing) input. Until you can vary the attachment piont of the canopy to the harness relative to the canopy, you're just dead weight in the harness (in a front to back sense). How to make the bar and attachemnt point, and how to operate it without killing lots of people? It might be impossible. I know I won't be one of the first 1000 people to try it, thats for sure.

They're really not. Some tandem canopies are tapered, and sporty in their nature, but the loadings are typically light, in the 1.0 to 1.2 range. Sure you can get them up to 1.5 or 1.6, but thats running into the limitations for suspended weight for the system. Most bigger TM's tend to prefer the bigger canopies anyway. Shutting down a canopy at 1.5 with extra luggage can be a handful.

Don't forget that the tightrope example involves the CG being above the rope, and it uses the force of gravity to introduce a side load to the rope when the CG shifts. If he could make his point with the performer hanging below the rope, then he might have something. Of course, the fact that his assertion creates a dynamic, non-sustainable situation sort of cancels out the whole point entirely (like you said). Actually, hang gliders are a perfect example of how the idea needs to work. You need a rigid structure to apply force to, using your weight as the counter. Canopies have no such structure.

Yeah, your right. Fuck the jumpers. Lets call all canopies the 'exactly what you need 135' and be done with it.

I have no doubt that there are jumpers who are both interested in, and capable of understanding, the information you are suggesting be presented. However, I also have no doubt that there are jumpers (maybe the majority) who either are not interested in that level of detail, cannot understand the factors presented, or will mis-construe how to apply the information. For this reason, I think you might be aiming a little high with your ideas. What needs to be presented is a basic explanation of the canopy's construction (cell number, x-bracing or airlocks, line type and design), along with a written description of the canopy's design intent. What question was the mfg. trying to answer when they developed the product? Is this the same question the jumper is asking when they are looking for a canopy? Additionally, this information needs to be applied to different wingloadings, and presented with a chart similar to the current warning label on PD canopies. This would give the jumper real-world information they could use when chosing a canopy. We have already discussed how canopies with similar design in the areas of cell number and taper can produce very different performing canopies, so providing that information does not answer the questions that jumpers need to consider when choosing a wing. For example, I would be a bit gun-shy to buy a 300hp, 3000lb. car for a first time driver. If, however, it was a heavy duty deisel truck for towing trailers, and had an empty weight of 5000lbs, aside from the gas guzzling problem, I'd feel much better about a newer driver behind the wheel. See? Same horsepower, two vastly different applications. Telling me it has 300hp is not enough, telling me what it's designed for, and how fast it will go is the real-world info I need. The terminology 'eliptical, semi-eliptical, and semi tapered' need to go away. There are no eliptical canopies (Firebolt excluded), and any term using the prefix 'semi' relies on A) having a 'full' or 'complete' standard to reference, and B) an indication of the magnitude of how 'semi' it is. Is it 50% of the reference or 75%?

Provided that A) the group is small enough, and that B) your tracking skills are such that you can do it without going head-low, during your actual track is a good time to check that the jumpers in your group are all headed far enough away from you. This sort of goes in line with checking your airspace before you dump, and you should absolutely check for other canopies during and just after your opening. Watching the other jumpers as you track just makes that process quicker as you already know pretty much where everyone is. This isn't directed at happythoughts per se, it's more of a public service for anyone reading the thread.

Use your eyeball. You can turn your still camera on and check the settings before you put the helmet on your head.

I wish. Last night I broke my rig down for it's winter cleaning/service, and I just walked in from being hit by the first snowflakes of the season. If you can wait unitl mid-January, I'll get back to you then.

This is the first flaw in your plan. Actually, it's also the last flaw in your plan. Pretty much the plan was doomed once your typed those words. It's like this plan: What if you could caputre bigfoot, and take him on a worldwide publicity tour? The proceeds would pay for the travel, and since you don't have to pay bigfoot (just feed him), you could make yoruself some money.

Well, at first it was about how releasing the brakes would stop a turn. That was suggested, and I commented that it should have no effect on the turn. As far as the other thing, my first impression would be that oversteer would be reduced with the brakes stowed, and I'll explain it this way: With the brakes stowed, you have increased drag, and the reduction of steady state airspeed that goes with it. Now grab a riser, and toss yourself into a turn. Your swinging under the wing will cause the canopy to turn/dive and pick up speed, however the amount of speed you will pick up will be limited by the drag of the stowed brakes. Your acceleration time will be reduced, as will all factors present with an increase in speed, oversteer being one of them. The point being is that with the brakes stowed, the flight envelope is reduced in its scope. The less speed you can pick up in a turn, the less the canopy will want to continue the turn, the less time you spend out from under the wing, etc. It all adds up to LESS oversteer, not more. As such, with the brakes unstowed, if you enter the same turn as before, the canopy will have a longer period of acceleration (before drag overcomes it), giving the pilot more time in the turn, and more time out from under the wing. At this point, it's basic physics: an object in motion will tend to stay in motion. My assertion is that the magnitude of that motion will dictate the degree to which it remains in motion. Push a toy car with 1 measure of force, it will roll 'x' feet. Push the same car with 2 measures of force, and it will roll a distance greater then 'x'. Turn a canopy to achieve airspeed 'a', and it will continue in the turn for a period of time 'y'. Turn the canopy to achieve an airspeed greater than 'a', and turn will continue for a period longer than 'y'. Does this sound right? Anyone?

I won't. What I will do is recognize that wearing a camera helmet is an additional factor to consider when planning a skydive. Hence, I'll arrange for a high enough pull altitude to accomadate my needs. It's not a regular jump, and as such, you cannot apply the principals of a regular jump. Cutting away your helmet will not ALWAYS be required when cutting away, so you cannot have a single procedure solution to your question.

It's going to be hard to tell what is happening from a video. I'd be much more interested in an explanation of how making your canopy fly faster, with no input toward the roll axis, will stop a rotation.

Try this 1. Deploy main 2. Wiggle head around trying to see the mal. 2a. If head moves freely, go to step 4. 2b. If head feels snagged, go to step 3. 3. Cutaway helmet, and peel it off your head. 4. Lean head away from risers, and chop main The catch is that you have to dump high enough to afford the time to really get a handle on your helmet situation.

Just wanted to say thanks to Hooknswoop for making my points for me while I was away from the computer. I agree with what he has said. If the brakes are properly stowed, they should have no effect on the roll axis if they are left stowed, or unstowed in a symetrical fashion. Any turn can be nuetralized with a counter-input provided that the canopy is not suffering from a malfunction of any kind. Rear riser input generally will provide the most immediate response, and having the brakes stowed will only increase the response.

You call it putting down, I call it providing accurate and valuable advice. Again, if you made choices that made sense, I'd have nothing to say. To that end, thank you for providing me a forum in which to speak, my hat is off to you.

Don't worry, I just came from the video forum, and according to his thread there, he'll be flying a camera, so we'll have whatever happens on video.

Thats good. But actually I haven't hit the ground hard at all. I have, on the other hand watched many. many folks (maybe like yourself) hit the ground all kinds of ways, resulting in all sorts of damage. Maybe the real answer is that you haven't hit the ground hard enough (yet). For the record, I do have a need to be a smartass, It's what I do. Say and do shit that makes sense, and I'll have nothing to say.